#include <stdio.h>

int main()
{
    int a = 0;
    printf("请输入一个整数：\n");
    scanf("%d",&a);
    int b = 0;

    b = a << 1;
    printf("a = %d\n",a);
    printf("a 的二进制数据向左移：\n");
    printf("b = %d\n",b);
    return 0;
}